The present invention relates to an inertial friction welded fluid pressure cylinder that includes a cylindrical tube welded to a base. The base has a retaining groove that receives a kerf formed during inertial welding. The groove is of selected size to trap foreign materials generated during the inertial welding process to prevent such foreign material from entering the interior of the cylindrical tube.
Inertial welding of hydraulic cylinder parts is well known. Some prior cylinders utilize an interior groove around the end cap to which the cylindrical tube is welded as a flash trap. U.S. Pat. No. 4,832,769 illustrates a friction welding flash trap seal that includes an end cap that has a plug which fits into the cylinder tube and the cylinder is necked down onto the plug after welding for complete sealing. The present invention avoids the need for necking down the cylindrical tube onto the interior plug of the base.
U.S. Pat. No. 3,618,196 discloses a flash trap for friction welding of cylinders that utilizes a pair of off-set shoulders to attempt to trap the weld flash.
A friction welded hydraulic actuator is shown in U.S. Pat. No. 3,596,570. A simple butt weld is shown between tube and the end cap.
A friction welding method is also illustrated in U.S. Pat. No. 3,444,611. The use of friction to seal thermo plastic parts is described in U.S. Pat. Nos. 2,853,118 and 3,690,088.
Problems with the weld flash have been present, as the prior art shows, but none of the art discloses methods to quickly, efficiency, and reliably eliminate problems with weld flash and other foreign materials through the use of a recessed groove of selected, appropriate size.